The size of maxillary sinus studied by CT.
Explore the source record for details and available documents.
Humans↗
Biomedical subjects
R G Newcombe
Publications and source records attributed to R G Newcombe.
A comparative study of stain removal with two electric toothbrushes and a manual brush.
Recent studies have suggested that a sonic electric toothbrush is more effective than a manual brush at removing extrinsic dental stain. There have been few studies of the comparative stain removal properties of different electric brushes. The study reported here was conducted to compare the efficacy of the sonic toothbrush (Sonicare) with an oscillating/rotating brush (Braun Oral-B Plaque Remover) and a conventional manual brush (Crest Complete). The study was a single-blind, randomized, cross-over design, balanced for residual effects and employing 24 subjects. Stain was enhanced over a 21-day period by twice-daily rinses with chlorhexidine and frequent intakes of tea and/or coffee. At the end of each period, tooth stain intensity and area, tongue stain intensity and area, lower lingual calculus and subjective tooth sensitivity were recorded together with preference for the brushes determined at the study's completion. Similar levels of tongue staining were recorded for the three periods, with no significant differences between the three groups. Tooth stain intensity, for most sites, was not significantly different between the three groups. For mean total stain area and for lingual and lingual interproximal sites, a significant reduction in stain was seen following use of the oscillating/rotating brush compared to the manual brush. The reductions in stain with the sonic brush were not significantly different from the manual brush. With the exception of maximum stain intensity, there were no significant differences between the oscillating/rotating and sonic brushes. Significantly less tooth sensitivity was found following use of the oscillating/rotating brush compared to both the manual and sonic brushes. All three brushes were found to be safe, but volunteer preference significantly and predominantly favored the oscillating/rotating brush. The results suggest that the oscillating/rotating brush is superior to a manual brush for stain removal.
Adult↗
Confidence intervals for a binomial proportion.
Explore the source record for details and available documents.
Binomial Distribution↗
Maternity blues and major endocrine changes: Cardiff puerperal mood and hormone study II.
OBJECTIVES: To define relation between mood and concentrations of progesterone and cortisol during perinatal period to test hypothesis that rapid physiological withdrawal of steroid hormones after delivery is associated with depression. DESIGN: Prospective study of primiparous women from two weeks before expected date of delivery to 35 days postpartum. SETTING: Antenatal clinic in university hospital, obstetric inpatient unit, patients' homes. SUBJECTS: 120 of 156 primiparous women interviewed. Remainder excluded because of major marital, socioeconomic, or medical problems or because caesarean section required. MAIN OUTCOME MEASURES: Concentrations of progesterone and cortisol in saliva samples; women's moods assessed by various scores for depression. RESULTS: Changes in salivary progesterone and cortisol concentrations were similar to those already characterised for plasma. Peak mean score for maternity blues (5.3 on Stein scale) was on day five postpartum (P < 0.02 compared with mean scores on other postpartum days). High postpartum scores for maternity blues were associated with high antenatal progesterone concentrations on day before delivery (P < 0.05), with high rate of rise of antenatal progesterone concentrations (P < 0.05), with decreasing progesterone concentrations from day of delivery to day of peak blues score (P > or = 0.01), and with low progesterone concentrations on day of peak blues score (P < 0.01). Seventy eight women were designated as having maternity blues (peak score > or = 8 on Stein scale) while 39 had no blues. Women with blues had significantly higher antenatal progesterone concentrations and lower postnatal concentrations than women without blues (geometric mean progesterone concentrations: one day before delivery 3860 pmol/l v 3210 pmol/l respectively, P = 0.03; ten days postpartum 88 pmol/l v 114 pmol/l, P = 0.048). Cortisol concentrations were not significantly associated with mood. CONCLUSION: Maternal mood in the days immediately after delivery is related to withdrawal of naturally occurring progesterone.
Adult↗
Transdermal nicotine for active ulcerative colitis.
BACKGROUND: Ulcerative colitis is largely a disease of nonsmokers. Because anecdotal reports suggest that smoking and nicotine may improve the symptoms of the disease, we examined the effect of nicotine as a supplemental treatment for ulcerative colitis. METHODS: We treated 72 patients with active ulcerative colitis with either transdermal nicotine patches or placebo patches for six weeks in a randomized, double-blind study. Incremental doses of nicotine were given; most patients tolerated doses of 15 to 25 mg per 24 hours. All the patients had been taking mesalamine, and 12 were receiving low doses of glucocorticoids; these medications were continued without change during the study. Clinical, sigmoidoscopic, and histologic assessments were made at base line and at the end of the study; symptoms were recorded daily on a diary card, and the clinician made a global assessment. Side effects and plasma nicotine and cotinine concentrations were monitored throughout the study. RESULTS: Seventeen of the 35 patients in the nicotine group had complete remissions, as compared with 9 of the 37 patients in the placebo group (P = 0.03). The patients in the nicotine group had greater improvement in the global clinical grade of colitis (P < 0.001) and the histologic grade (P = 0.03), lower stool frequency (a difference of 1.6 stools daily; P = 0.008), less abdominal pain (P = 0.05), and less fecal urgency (P = 0.009). More patients in the nicotine group had side effects (23, vs. 11 in the placebo group; P = 0.002), the most common of which were nausea, lightheadedness, headache, and sleep disturbance. Withdrawals due to ineffective therapy were more common in the placebo group (3 vs. 8, P = 0.12). CONCLUSIONS: The addition of transdermal nicotine to conventional maintenance therapy improves symptoms in patients with ulcerative colitis.
Administration, Cutaneous↗
Cigarette smoking is not a risk factor in atopic dermatitis.
BACKGROUND: In recent years several diseases have been shown to have a relationship with smoking. Psoriasis is largely a disease of smokers, whereas acne appears to be associated with not smoking. METHODS: One hundred and fifty patients with atopic dermatitis were sent a postal questionnaire on smoking habits and the results were compared with those from matched controls in the local community. RESULTS: One hundred and twenty-seven patients (85%) completed the questionnaire. There was no apparent difference in the prevalence of current smokers amongst atopic dermatitis patients compared with controls (odds ratio = 1.1, 95% confidence limits 0.65-1.86, P = 0.8). CONCLUSIONS: There was no significant difference between the smoking prevalence of patients with atopic dermatitis and matched controls.
Dermatitis, Atopic↗
Dose response of chlorhexidine against plaque and comparison with triclosan.
The optimum dose of chlorhexidine delivered by mouthrinse, which balances efficacy against local side-effects, is generally considered to be in the region of 20 mg 2 x daily. Unfortunately, there have been few dose-response studies for chlorhexidine mouthrinses and for these, only limited details are published. The aims of this study were to determine the dose response of chlorhexidine to plaque inhibition and position a 0.1% triclosan rinse within this model. 28 subjects took part in this 7-treatment, double-blind, randomised cross-over 4-day plaque regrowth study. The rinses were 0.01%, 0.05%, 0.1% and 0.2% chlorhexidine, 0.1% triclosan and minus active controls for chlorhexidine and triclosan. On day 1 from a zero plaque baseline, volunteers suspended tooth-cleaning and commenced supervised 2 x daily rinsing with 10 ml volumes of the allocated rinses. On Day 5, plaque was scored by index and area. Treatment differences between the 7 rinses were highly significant. A clear dose-response pattern was seen for chlorhexidine with mean plaque scores decreasing with increasing dose. Even at 0.01%, chlorhexidine showed considerable and significant plaque inhibition compared to control. Triclosan at 0.1% showed limited plaque inhibition and less than 0.01% chlorhexidine. The findings of this study suggest that consideration could be given to low concentration chlorhexidine rinses as adjuncts to oral hygiene.
Adult↗
The magnitude and duration of the effects of some mouthrinse products on salivary bacterial counts.
The persistence of action or substantivity of an antimicrobial agent in the mouth relates to the plaque inhibitory action of that compound. Substantivity can be assessed by measuring the magnitude and duration of the fall in salivary bacteria following single rinses with antimicrobials. This was a randomised single-blind, cross-over study measuring the effects of single 60-s rinses of 5 mouthwash products on salivary bacterial counts in 14 healthy human volunteers. Effects over a 7-h period were compared with a chlorhexidine rinse product (positive control) and saline (negative control). All but one rinse, containing cetylpyridinium chloride (CPC), significantly reduced bacterial counts compared to saline up to 5-7 h. No rinse produced the magnitude or duration of effect noted for chlorhexidine and decrements from baseline, with one exception, were highly significantly lower than with the chlorhexidine product. Comparing the 2 CPC rinses, the findings suggest that the activity of one product was vitiated by some other ingredient. The triclosan/copolymer, the essential oil/phenolic and one CPC products exhibited similar persistence. In those cases where information is available, these data are consistent with comparative plaque inhibitory findings for the products or their active ingredients. Again, it is concluded that the method is a useful screening and comparison test for the potential plaque inhibitory activity of antimicrobial oral hygiene products.
Adult↗
A comparison of cetylpyridinium chloride, triclosan and chlorhexidine mouthrinse formulations for effects on plaque regrowth.
A relatively small number of agents are used in mouthrinse products, although the possible variability in the final formulations is enormous. The aim of this study was to compare equal concentrations of 3 antimicrobial agents, in simple formulations, for plaque inhibition. This 4-day plaque regrowth study was a 5-cell, randomised, double blind cross-over design, involving 20 healthy human volunteers. The mouthrinse formulations were aqueous 0.05% solutions of cetylpyridinium chloride (CPC), chlorhexidine and triclosan, together with a 0.1% CPC and a minus active control rinse. On Day 1, from a zero plaque baseline, volunteers ceased normal oral hygiene and rinsed 2x daily for 1 min. with 10-ml volumes of the allocated rinses. On Day 5, plaque was scored by index and area. All rinses produced lower mean plaque values compared to control, but unlike the CPC and chlorhexidine rinses, the differences with triclosan did not always reach significance. The CPC and chlorhexidine rinses were always significantly more effective than the triclosan rinse. The greatest plaque inhibition was with 0.1% CPC although rarely significantly greater than the 0.05% CPC and chlorhexidine rinses which were similar in efficacy. The results indicate that further studies on lower concentration chlorhexidine solutions are warranted.
Adult↗
Thickness of adherent mucus gel on colonic mucosa in humans and its relevance to colitis.
The thickness of adherent mucus gel on the surface of colonic mucosa was measured in surgically resected specimens from 46 'control' patients most of whom had carcinoma of the colon; 12 were from right colon, 17 left colon, and 21 from rectum. In addition specimens were examined from 17 patients with ulcerative colitis and 15 patients with Crohn's disease. In controls a continuous layer of mucus was readily seen on specially prepared sections viewed by phase contrast illumination. Mean values for right and left colon and rectum were 107 (48), 134 (68), and 155 (54) microns respectively with a significant difference between right colon and rectum (p = 0.015). Values in ulcerative colitis showed greater variation and in those areas with acute inflammation mucosa was denuded of the mucus layer. In contrast, values for Crohn's disease were normal or greater than normal in thickness--right colon 190 (83) microns compared with 107 48 microns, p = 0.0093. A series of validation experiments are described for the method used to measure mucus thickness. The possible role of mucus in the pathogenesis of inflammatory bowel disease is discussed.
Adolescent↗
Controlled trial of anti-tuberculous chemotherapy for two years in Crohn's disease.
One hundred and thirty patients with active symptoms of Crohn's disease were treated in a double blind randomised controlled trial with rifampicin, isoniazid, and ethambutol, or identical placebos for up to two years. All other treatment considered necessary was continued. Analyses were based on 126 patients, 63 in each treatment group. Thirty seven in the active and 30 in the placebo group had previous surgical procedures. There was no difference in concomitant treatment between the two groups. Thirty in the active and 46 in the placebo groups were taking corticosteroids at entry to the trial. Forty eight of 63 patients in the active and 49 of 63 in the placebo group, completed at least 12 months' therapy. Reasons for early withdrawal included pregnancy, adverse reaction, and failure to comply. There was no significant difference in the mean number of months completed between the two groups. Nineteen adverse reactions were recorded for 17 patients in the active group compared with three reactions in patients on placebo. All of the nine patients withdrawn early because of adverse reactions were in the active group. Fifteen patients on active treatment and 14 on placebo had surgery during the trial with no difference in the type of surgery required between the groups. Radiological assessments based on 98 patients at the end of the trial showed no significant differences between groups in changes of extent of disease. More patients developed strictures on placebo compared with active treatment but without a statistically significant difference. No differences were found between groups for the total prednisolone dose or the number of days on which prednisolone dose was 10 mg or above. Serial measurements of body weight and Crohn's disease activity index (CDAI) together with blood values for albumin, haemoglobin, white cell count, and platelets showed no consistent different differences between groups. There were occasional significant differences for some of these values between groups, which were not sustained. The trail provides little evidence of tangible benefit from the trail treatment.
Adolescent↗
Research in orthodontics--a statistical perspective.
Explore the source record for details and available documents.
Clinical Trials as Topic↗
Efficacy of mouthrinses in inhibiting the development of supragingival plaque over a 4-day period of no oral hygiene.
This study was a first stage evaluation of the plaque inhibitory properties of an experimental cetylpyridinium chloride (CPC)/essential oil mouthrinse. The study was a formulation, not ingredient, evaluation and comparisons were made with established mouthrinse products. The 5 rinses tested were: the experimental formulation; a triclosan/copolymer prebrushing mouthrinse; two negative control rinses, which differed only in color; and as a positive control, a 0.2% chlorhexidine mouthrinse. The study used a 5 cell, 4-day plaque regrowth, double-blind crossover design in which 15 subjects participated. Allocation of mouthrinse sequences was accomplished using 3 replicates of a 5 x 5 Latin square, incorporating balance for carryover. On Day 1, subjects received a scaling and polishing to reduce plaque, ceased toothcleaning, and commenced rinsing twice daily, under supervision, with the randomly assigned rinse. Rinsing time for the experimental and one negative control rinse was 30 seconds and for the other rinses was 60 seconds. On Day 5, plaque was scored by both index and area. Differences in plaque regrowth between the rinse groups were highly significant. The order of efficacy from the most effective was: chlorhexidine rinse (positive control); experimental CPC/essential oil rinse; triclosan/copolymer rinse; and the negative control rinses. From the calculated confidence intervals each rinse differed significantly from each other rinse, except for the two negative control rinses which were comparable to each other. Proportionately, the CPC/essential oil rinse was positioned 30 to 50% between the triclosan/copolymer rinse and the chlorhexidine (positive control). These findings suggest that the CPC/phenolic rinse would seem worthy of further evaluation for adjunctive benefits to oral hygiene.
Adult↗
Dentine hypersensitivity: a clinical trial to compare 2 strontium densensitizing toothpastes with a conventional fluoride toothpaste.
A considerable number of varied agents are apparently effective in the treatment of dentine hypersensitivity. In particular, the literature supports the efficacy of fluoride and strontium containing formulations. Despite this, comparisons between strontium products are relatively few in number and surprisingly there are almost no evaluations of these products against "bench mark," conventional commercial fluoride toothpastes. This study was a double-blind parallel group comparison of two strontium-based desensitizing toothpaste products and a conventional fluoride product in the treatment of dentine hypersensitivity. A total of 119 patients completed the 12-week study and from them, sensitivity gradings were obtained at baseline, 1, 4, 8, and 12 weeks. Sensitivity was scored in response to cold air, a thermal probe at 0 degree C, and scratching with a dental probe. Patients also graded their overall sensitivity at each visit, using a visual analogue scale and the effects of treatment on completion. Plaque and gingivitis indices were recorded at each visit. There was an overall and progressive reduction in all sensitivity parameters in the 3 groups with no significant differences between the treatments. Plaque and gingivitis scores were already relatively low in this patient group at baseline but improved further as the study continued. The improvements, however, were comparable in the 3 groups. Under the conditions of this clinical trial the 2 desensitizing toothpastes showed similar reductions, but no greater than that observed in the conventional fluoride toothpaste. There is perhaps the need for further evaluations of desensitizing formulations using conventional fluoride products as controls rather than minus active or placebo formulations.
Adult↗
A study of a pre-brushing mouthrinse as an adjunct to oral hygiene.
A previous clinical screening study demonstrated that a cetylpyridinium chloride (CPC) essential oil mouthrinse inhibited plaque regrowth to a significantly greater extent than a negative control or a triclosan/copolymer rinse when used without toothbrushing. The purpose of this study was to evaluate the same ingredient combination as a pre-brushing rinse over a 6-week period. The study employed a 4 group parallel design with a minimum of 50 subjects per group. Subjects with a minimum baseline plaque index of 1.95 were recruited. The formulations employed were two variations of a CPC/essential oil rinse, a triclosan/copolymer product, and a hydroalcohol negative control. Subjects were rendered plaque free at baseline and then rinsed twice daily before toothbrushing with their allocated product. Plaque was scored at 6 days and 6 weeks. Plaque scores were reduced at 6 days compared to baseline but there were no significant differences between any of the groups. At 6 weeks, plaque scores were significantly lower in both CPC/essential oil groups compared to control. Although both CPC/essential oil groups showed plaque scores which were lower than the triclosan group, in only one of the groups was the difference significant. The triclosan product was not significantly different from control. The results support the previous findings that a CPC/essential oil rinse could be a useful adjunct to oral hygiene when used prior to normal toothbrushing.
Adolescent↗
Smoking and ulcerative colitis: a community study.
Smoking habits of patients with ulcerative colitis, diagnosed in the City of Cardiff between the 1st of January 1978 and the 31st of December 1987 were examined. There was a significant deficit of current smokers, an excess of life-long non-smokers and ex-smokers compared with the general population. Men who had previously smoked presented with colitis later than life long non-smokers (mean age difference 16.1 years). The proportion of ex-smokers in this group of patients with colitis was more than twice that expected in the general population. The interval between cessation of smoking and subsequent onset of colitis in ex-smokers was relatively short and in more than half of them occurred within 8 years. There was no significant difference in the frequency of colectomy or the extent of disease among smokers, ex-smokers or life-long non-smokers with ulcerative colitis.
Adult↗
Detection of latent variegate porphyria by fluorescence emission spectroscopy of plasma.
The plasma of patients with overt variegate porphyria contains porphyrin with a fluorescence emission maximum at about 626 nm, which is diagnostic for the condition. We have evaluated qualitative fluorescence emission scanning of saline-diluted plasma as a method for the identification of asymptomatic carriers of the gene for variegate porphyria. Plasma from 36 unrelated patients with variegate porphyria, 136 of their asymptomatic first- and second-degree relatives aged 15 years or over, and 322 normal subjects was scanned. An emission maximum between 621 and 627 nm was observed in the 36 patients with variegate porphyria and 54 of their relatives, but not in any normal subject, nor in 56 patients with other types of porphyria. For the detection of asymptomatic adult carriers of the gene for variegate porphyria, fluorescence emission scanning of plasma appears to be 100% specific, with a sensitivity of 86% (95% confidence interval 71-98%). In contrast, the sensitivity of faecal porphyrin analysis as a test for adult gene carriers was 36%. These results suggest that fluorescence emission scanning of plasma should replace faecal porphyrin analysis as the test of first choice for this purpose.
Adolescent↗